Various abbreviations that may appear in the specification and/or in the drawing figures are defined as follows:
3GPP third generation partnership project
BCH broadcast channel
BW bandwidth
CIR carrier per interference ratio
DL downlink (eNB towards UE)
eNB EUTRAN Node B (evolved Node B)
EUTRAN evolved UTRAN (LTE)
FSU flexible spectrum use
HO handover
ID identification
IMT international mobile telecommunications
IMT-A advanced IMT
L1 Layer 1 or physical (PHY) layer
LA local area
LTE long term evolution
LTE-A LTE advanced
MME mobility management entity
Node B base station
OFDMA orthogonal frequency division multiple access
PHY physical
RAN radio access network
Rel. release
RSP redirecting synchronization pointer
RSSI carrier received signal strength indicator
SC-FDMA single carrier, frequency division multiple access
S-GW serving gateway
SID system identification
TDD time division duplex
UE user equipment
UL uplink (UE towards eNB)
UTRAN universal terrestrial radio access network
WG working group
A proposed communication system known as evolved UTRAN (E-UTRAN, also referred to as UTRAN-LTE or as E-UTRA) is currently under development within the 3GPP. As currently specified the DL access technique will be OFDMA, and the UL access technique will be SC-FDMA.
One specification of interest is 3GPP TS 36.300, V8.3.0 (2007-12), 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Access Network (E-UTRAN); Overall description; Stage 2 (Release 8), which is incorporated by reference herein in its entirety. This system may be referred to for convenience as LTE Rel-8, or simply as Rel-8, and may also be referred to herein as being an earlier version of a communication standard.
Of particular interest herein is the 3GPP LTE Release 9 (and beyond towards future IMT-A systems), referred to herein for convenience simply as Rel-9, or as LTE-Advanced (LTE-A), and may also be referred to herein as being a later version of a communication standard. Of additional interest herein are LA deployment scenarios using TDD in a scalable bandwidth (of up to, for example, 100 MHz) with flexible spectrum use (FSU). This system concept may be referred to herein for convenience as Rel-9 LA.
It has been decided that LTE Rel-8 UEs should be able to operate in the LTE-A system. General reference in this regard may be made to 3GPP TSG RAN WG1 Meeting #53, Kansas City, USA, May 5-9, 2008, R1-081948, Proposals for LTE-Advanced Technologies, NTT DoCoMo, Inc, which was attached as Exhibit A to the priority document U.S. 61/130,786 (filed on Jun. 3, 2008).
In evolving towards Rel-9, maintaining backwards compatibility with Rel-8 (E-UTRAN) is an important issue. For example, a Rel-8 UE should be able to access a corresponding Rel-9 system, and a Rel-9 UE should be able to access corresponding Rel-8 system. Provided that a Rel-8 UE is capable of operating in a scalable system bandwidth of up to 20 MHz (e.g., 10 MHz TDD or 20 MHz TDD) as specified in 3GPP, and that this BW is then scaled up to 100 MHz for Rel-9, the Rel-9 radio may possibly be structured as a scalable multi-carrier system having at least one Rel-8-compatible carrier.
As can be appreciated, a number of problems can arise in attempting to maintain compatibility between Rel-8 and Rel-9 systems.
Other publications that may be interest herein include RP-080137, Proposed SID on LTE-Advanced, NTT DoCoMo, 3GPP RAN#39, Puerto Vallarta, Mexico, 4-7 Mar. 2008, attached as Exhibit B to the priority document, and R3-080812, Solution(s) to the 36.902's Automated Configuration of Physical Cell Identity Use Case, Nokia Siemens Networks, Nokia, Shenzen, China, April 2008, attached as Exhibit C to the priority document.